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1.
Sci Total Environ ; 870: 161000, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36690095

RESUMO

Stakeholders involved in actions to reduce the use and the impacts on the environment or human health of pesticides need operational tools to assess crop protection strategies in regard to these impacts. I-Phy3 brings together all improvements introduced since the first version of the indicator to better meet user's needs and requirements of integrating processes. I-Phy3 was deeply modified to ensure its predictive quality. I-Phy 3 is structured in three levels of aggregation in form of hierarchical fuzzy decision trees designed with the CONTRA method. At the 1st level, five basic subindicators assess the risk of contamination (RC) for the different transfer pathways involved in surface water, ground water and atmosphere contamination: leaching, runoff, drainage, drift, volatilization. At the 2nd level, RC subindicators are aggregated with a toxicity variable (human or aquatic) in a risk indicator. At the 3rd level, the global indicator I-Phy3 results from the aggregation of three risk indicators for groundwater, surface waters and air. I-Phy3 yielded better validation results than its previous versions. This effort to assess the predictive quality of the indicator should be pursued and completed by a feasibility and utility test by end-users. A subindicator on risk of soil contamination is a gap which remains to fill.

2.
Knee Surg Sports Traumatol Arthrosc ; 29(6): 1701-1708, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32740878

RESUMO

PURPOSE: A histological study of a structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament. METHODS: Bilateral fresh-frozen cadaveric knees of two male donors (age 71 and 76 years) with no history of prior knee injury were examined. All dissections were performed by one experienced orthopaedic surgeon. Haematoxylin and Eosin staining was used to reveal tissue morphology. Goldner trichrome staining was used to evaluate the connective tissue. S100 and PGP 9.5 labelling were used for immunohistochemical analysis. RESULTS: In all cadaveric knees, a structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament was identified. Histological analysis confirmed the ligamentous nature of this structure. Furthermore, Golgi tendon organs were observed within the ligamentous structure. CONCLUSION: This is the first study showing the presence of mechanoreceptors within the ligamentous structure between the posterior horn of the lateral meniscus and the anterior cruciate ligament. The ligamentous structure could contribute to stability of the knee by providing proprioceptive input, while preservation of the ligamentous structure might ensure a better functional outcome after surgery.


Assuntos
Ligamento Cruzado Anterior/citologia , Mecanorreceptores , Meniscos Tibiais/citologia , Idoso , Ligamento Cruzado Anterior/inervação , Lesões do Ligamento Cruzado Anterior/epidemiologia , Cadáver , Humanos , Traumatismos do Joelho/epidemiologia , Articulação do Joelho , Masculino , Meniscos Tibiais/inervação , Propriocepção
3.
J Biol Chem ; 294(13): 5121-5136, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30718282

RESUMO

Viperin (also known as radical SAM domain-containing 2 (RSAD2)) is an interferon-inducible and evolutionary conserved protein that participates in the cell's innate immune response against a number of viruses. Viperin mRNA is a substrate for endoribonucleolytic cleavage by RNase mitochondrial RNA processing (MRP) and mutations in the RNase MRP small nucleolar RNA (snoRNA) subunit of the RNase MRP complex cause cartilage-hair hypoplasia (CHH), a human developmental condition characterized by metaphyseal chondrodysplasia and severe dwarfism. It is unknown how CHH-pathogenic mutations in RNase MRP snoRNA interfere with skeletal development, and aberrant processing of RNase MRP substrate RNAs is thought to be involved. We hypothesized that viperin plays a role in chondrogenic differentiation. Using immunohistochemistry, real-time quantitative PCR, immunoblotting, ELISA, siRNA-mediated gene silencing, plasmid-mediated gene overexpression, label-free MS proteomics, and promoter reporter bioluminescence assays, we discovered here that viperin is expressed in differentiating chondrocytic cells and regulates their protein secretion and the outcome of chondrogenic differentiation by influencing transforming growth factor ß (TGF-ß)/SMAD family 2/3 (SMAD2/3) activity via C-X-C motif chemokine ligand 10 (CXCL10). Of note, we observed disturbances in this viperin-CXCL10-TGF-ß/SMAD2/3 axis in CHH chondrocytic cells. Our results indicate that the antiviral protein viperin controls chondrogenic differentiation by influencing secretion of soluble proteins and identify a molecular route that may explain impaired chondrogenic differentiation of cells from individuals with CHH.


Assuntos
Quimiocina CXCL10/metabolismo , Condrogênese , Proteínas/metabolismo , Animais , Linhagem Celular , Técnicas de Silenciamento de Genes , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Proteínas/análise , Proteínas/genética , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta/metabolismo
4.
Brain Behav Immun ; 77: 92-100, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30593840

RESUMO

INTRODUCTION: The spleen is hypothesized to play a role in the autonomic nervous system (ANS)-mediated control of host defence, but the neuroanatomical evidence for this assumption rests on a sparse number of studies, which mutually disagree with respect to the existence of cholinergic or vagal innervation. METHODS: We conducted an immuno- and enzyme-histochemical study of the innervation of the human spleen using a complete hilum-embedding approach to ensure that only nerves that entered or left the spleen were studied, and that all splenic nerves were included in the sampled area. Furthermore, a complete embedded spleen was serially sectioned to prepare a 3D reconstruction of the hilar nerve plexus. RESULTS: All detected nerves entering the spleen arise from the nerve plexus that surrounds branches of the splenic artery and are catecholaminergic. Inside the spleen these nerves continue within the adventitia of the white pulpal central arteries and red pulpal arterioles. Staining for either choline acetyltransferase or acetylcholinesterase did not reveal any evidence for cholinergic innervation of the human spleen, irrespective of the type of fixation (regularly fixed, fresh-frozen post-fixed or fresh-frozen cryoslides). Furthermore, no positive VIP staining was observed (VIP is often co-expressed in postganglionic parasympathetic nerves). CONCLUSION: Our comprehensive approach did not produce any evidence for a direct cholinergic (or VIP-ergic) innervation of the spleen. This finding does not rule out (indirect) vagal innervation via postganglionic non-cholinergic periarterial fibres.


Assuntos
Baço/inervação , Idoso , Idoso de 80 Anos ou mais , Sistema Nervoso Autônomo/fisiologia , Colina O-Acetiltransferase , Feminino , Técnicas Histológicas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso Parassimpático , Sistema Nervoso Simpático , Nervo Vago/fisiologia
5.
Sci Rep ; 8(1): 11697, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-30076368

RESUMO

Communicating fibres between the phrenic nerve and sympathetic nervous system may exist, but have not been characterized histologically and immunohistochemically, even though increased sympathetic activity due to phrenic nerve stimulation for central sleep apnoea may entail morbidity and mortality. We, therefore, conducted a histological study of the phrenic nerve to establish the presence of catecholaminergic fibres throughout their course. The entire phrenic nerves of 35 formalin-fixed human cadavers were analysed morphometrically and immunohistochemically. Furthermore, the right abdominal phrenic nerve was serially sectioned and reconstructed. The phrenic nerve contained 3 ± 2 fascicles in the neck that merged to form a single fascicle in the thorax and split again into 3 ± 3 fascicles above the diaphragm. All phrenic nerves contained catecholaminergic fibres, which were distributed homogenously or present as distinct areas within a fascicle or as separate fascicles. The phrenicoabdominal branch of the right phrenic nerve is a branch of the celiac plexus and, therefore, better termed the "phrenic branch of the celiac plexus". The wall of the inferior caval vein in the diaphragm contained longitudinal strands of myocardium and atrial natriuretic peptide-positive paraganglia ("caval bodies") that where innervated by the right phrenic nerve.


Assuntos
Vias Autônomas/anatomia & histologia , Diafragma/inervação , Nervo Frênico/anatomia & histologia , Abdome/anatomia & histologia , Abdome/inervação , Feminino , Humanos , Masculino , Pescoço/inervação , Tórax/inervação
6.
Physiol Rep ; 6(11): e13717, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29890043

RESUMO

Endothelial arginase 1 was ablated to assess whether this prevents hyperglycemia-induced endothelial dysfunction by improving arginine availability for nitric oxide production. Endothelial Arg1-deficient mice (Arg1-KOTie2 ) were generated by crossing Arg1fl/fl (controls) with Tie2Cretg/- mice and analyzed by immunohistochemistry, measurements of hemodynamics, and wire myography. Ablation was confirmed by immunohistochemistry. Mean arterial blood pressure was similar in conscious male control and Arg1-KOTie2 mice. Depletion of circulating arginine by intravenous infusion of arginase 1 or inhibition of nitric oxide synthase activity with L-NG -nitro-arginine methyl ester increased mean arterial pressure similarly in control (9 ± 2 and 34 ± 2 mmHg, respectively) and Arg1-KOTie2 mice (11 ± 3 and 38 ± 4 mmHg, respectively). Vasomotor responses were studied in isolated saphenous arteries of 12- and 34-week-old Arg1-KOTie2 and control animals by wire myography. Diabetes was induced in 10-week-old control and Arg1-KOTie2 mice with streptozotocin, and vasomotor responses were studied 10 weeks later. Optimal arterial diameter, contractile responses to phenylephrine, and relaxing responses to acetylcholine and sodium nitroprusside were similar in normoglycemic control and Arg1-KOTie2 mice. The relaxing response to acetylcholine was dependent on the availability of extracellular l-arginine. In the diabetic mice, arterial relaxation responses to endothelium-dependent hyperpolarization and to exogenous nitric oxide were impaired. The data show that endothelial ablation of arginase 1 in mice does not markedly modify smooth muscle and endothelial functions of a resistance artery under normo- and hyperglycemic conditions.


Assuntos
Arginase/metabolismo , Diabetes Mellitus/metabolismo , Diabetes Mellitus/fisiopatologia , Células Endoteliais/metabolismo , Vasodilatação , Animais , Arginase/genética , Pressão Arterial , Artérias/fisiopatologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo
7.
Lasers Surg Med ; 50(9): 948-960, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29756651

RESUMO

BACKGROUND: During several anesthesiological procedures, needles are inserted through the skin of a patient to target nerves. In most cases, the needle traverses several tissues-skin, subcutaneous adipose tissue, muscles, nerves, and blood vessels-to reach the target nerve. A clear identification of the target nerve can improve the success of the nerve block and reduce the rate of complications. This may be accomplished with diffuse reflectance spectroscopy (DRS) which can provide a quantitative measure of the tissue composition. The goal of the current study was to further explore the morphological, biological, chemical, and optical characteristics of the tissues encountered during needle insertion to improve future DRS classification algorithms. METHODS: To compare characteristics of nerve tissue (sciatic nerve) and adipose tissues, the following techniques were used: histology, DRS, absorption spectrophotometry, high-resolution magic-angle spinning nuclear magnetic resonance (HR-MAS NMR) spectroscopy, and solution 2D 13 C-1 H heteronuclear single-quantum coherence spectroscopy. Tissues from five human freshly frozen cadavers were examined. RESULTS: Histology clearly highlights a higher density of cellular nuclei, collagen, and cytoplasm in fascicular nerve tissue (IFAS). IFAS showed lower absorption of light around 1200 nm and 1750 nm, higher absorption around 1500 nm and 2000 nm, and a shift in the peak observed around 1000 nm. DRS measurements showed a higher water percentage and collagen concentration in IFAS and a lower fat percentage compared to all other tissues. The scattering parameter (b) was highest in IFAS. The HR-MAS NMR data showed three extra chemical peak shifts in IFAS tissue. CONCLUSION: Collagen, water, and cellular nuclei concentration are clearly different between nerve fascicular tissue and other adipose tissue and explain some of the differences observed in the optical absorption, DRS, and HR-NMR spectra of these tissues. Some differences observed between fascicular nerve tissue and adipose tissues cannot yet be explained but may be helpful in improving the discriminatory capabilities of DRS in anesthesiology procedures. Lasers Surg. Med. 50:948-960, 2018. © 2018 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Tecido Nervoso/diagnóstico por imagem , Tecido Nervoso/patologia , Imagem Óptica , Análise Espectral , Idoso , Idoso de 80 Anos ou mais , Feminino , Técnicas Histológicas , Humanos , Masculino , Técnicas de Cultura de Tecidos
8.
J Nurs Manag ; 26(2): 200-208, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29318699

RESUMO

AIM(S): To understand nurses' experiences of injustice in the workplace and to identify the impact of injustice on well-being. BACKGROUND: Little is known about how nurses view injustice or its effects on their well-being, although research indicates that such perceptions are central to workplace practices such as performance management and outcomes such as employee well-being. METHOD(S): A qualitative study was conducted with semi-structured interviews for nurses employed in Australian public hospitals. Data were analysed using content analysis. RESULTS: Experiences of injustice and unfairness negatively impacted on performance and the personal health of nurses. Unfair treatment was met with reduced effort and commitment. CONCLUSION(S): This study provides valuable insights into how nurses perceive and experience injustice at work and supports the link between injustice and nurses' decreased well-being and effectiveness. IMPLICATIONS FOR NURSING MANAGEMENT: Implications for nurse managers include the need for managers to engage in regular conversations regarding systemic barriers to performance and implementing performance management as an ongoing dialogue designed for employee voice and relationship management. This process also suggests a need for leadership development in nursing management. Using such steps and strategies would significantly enhance best practice in nursing management.


Assuntos
Satisfação no Emprego , Local de Trabalho/psicologia , Local de Trabalho/normas , Adulto , Idoso , Austrália , Feminino , Humanos , Liderança , Masculino , Pessoa de Meia-Idade , Papel do Profissional de Enfermagem/psicologia , Reorganização de Recursos Humanos/tendências , Pesquisa Qualitativa
9.
BMC Pulm Med ; 17(1): 158, 2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29183288

RESUMO

BACKGROUND: (Over-)expression of arginase may limit local availability of arginine for nitric oxide synthesis. We investigated the significance of arginase1 (ARG1) for the development of airway hyperresponsiveness (AHR) and lung inflammation in female mice with ovalbumin (OVA)-induced allergic asthma. METHODS: Arg1 was ablated in the lung by crossing Arg1 fl/fl and Tie2Cre tg/- mice. OVA sensitization and challenge were conducted, and AHR to methacholine was determined using the Flexivent system. Changes in gene expression, chemokine and cytokine secretion, plasma IgE, and lung histology were quantified using RT-qPCR, ELISA, and immunohistochemistry, respectively. RESULTS: Arg1 ablation had no influence on the development of OVA-induced AHR, but attenuated OVA-induced increases in expression of Arg2 and Nos2, Slc7a1, Slc7a2, and Slc7a7 (arginine transporters), Il4, Il5 and Il13 (TH2-type cytokines), Ccl2 and Ccl11 (chemokines), Ifng (TH1-type cytokine), Clca3 and Muc5ac (goblet cell markers), and OVA-specific IgE. Pulmonary IL-10 protein content increased, but IL-4, IL-5, IL-13, TNFα and IFNγ content, and lung histopathology, were not affected. Arg1 elimination also decreased number and tightness of correlations between adaptive changes in lung function and inflammatory parameters in OVA/OVA-treated female mice. OVA/OVA-treated female mice mounted a higher OVA-IgE response than males, but the correlation between lung function and inflammation was lower. Arg1-deficient OVA/OVA-treated females differed from males in a more pronounced decline of arginine-metabolizing and -transporting genes, higher plasma arginine levels, a smaller OVA-specific IgE response, and no improvement of peripheral lung function. CONCLUSION: Complete ablation of Arg1 in the lung affects mRNA abundance of arginine-transporting and -metabolizing genes, and pro-inflammatory genes, but not methacholine responsiveness or accumulation of inflammatory cells.


Assuntos
Arginase/genética , Asma/genética , Asma/metabolismo , Citocinas/genética , RNA Mensageiro/metabolismo , Resistência das Vias Respiratórias/genética , Sistema y+ de Transporte de Aminoácidos/genética , Sistema y+L de Transporte de Aminoácidos , Sistemas de Transporte de Aminoácidos Básicos/genética , Animais , Arginase/metabolismo , Arginina/sangue , Asma/induzido quimicamente , Asma/fisiopatologia , Transportador 1 de Aminoácidos Catiônicos/genética , Citocinas/metabolismo , Feminino , Expressão Gênica , Imunoglobulina E/sangue , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Células Mieloides , Óxido Nítrico Sintase Tipo II/genética , Ovalbumina , Pneumonia/genética , Pneumonia/patologia , Mecânica Respiratória/genética
10.
Sci Total Environ ; 605-606: 655-665, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28675875

RESUMO

Stakeholders need operational tools to assess crop protection strategies in regard to environmental impact. The need to assess and report on the impacts of pesticide use on the environment has led to the development of numerous indicators. However, only a few studies have addressed the predictive quality of these indicators. This is mainly due to the limited number of datasets adapted to the comparison of indicator outputs with pesticide measurement. To our knowledge, evaluation of the predictive quality of pesticide indicators in comparison to the quality of water as presented in this article is unprecedented in terms of the number of tested indicators (26 indicators and the MACRO model) and in terms of the size of datasets used (data collected for 4 transfer pathways, 20 active ingredients (a.i.) for a total of 1040 comparison points). Results obtained on a.i. measurements were compared to the indicator outputs, measured by: (i) correlation tests to identify linear relationship, (ii) probability tests comparing measurements with indicator outputs, both classified in 5 classes, and assessing the probability i.e. the percentage of correct estimation and overestimation (iii) by ROC tests estimating the predictive ability against a given threshold. Results showed that the correlation between indicator outputs and the observed transfers are low (r<0.58). Overall, more complex indicators taking into account the soil, the climatic and the environmental aspects yielded comparatively better results. The numerical simulation model MACRO showed much better results than those for indicators. These results will be used to help stakeholders to appropriately select their indicators, and will provide them with advice for possible use and limits in the interpretation of indicator outputs.

11.
Obes Res Clin Pract ; 7(1): e8-13, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24331678

RESUMO

Adipocyte size is a major modulator of endocrine functioning of adipose tissue and methods allowing accurate determination of adipocyte size are important to study energy metabolism. The aim of this study was to assess the relative shrinkage of adipocytes before and after weight loss by comparing adipose tissue from the same subjects embedded in paraffin and plastic. 18 healthy subjects (5 males and 13 females) aged 20-50 y with a BMI of 28-38 kg/m² followed a very low energy diet for 8 weeks. Adipose tissue biopsies were taken prior to and after weight loss and were processed for paraffin and plastic sections. Parameters of adipocyte size were determined with computer image analysis. Mean adipocyte size was smaller in paraffin compared to plastic embedded tissue both before (66 ± 4 vs. 103 ± 5 µm, P < 0.001) as after weight loss (62 ± 4 vs. 91 ± 5 µm, P < 0.001). Relative shrinkage of adipocytes in paraffin embedded tissue in proportion to plastic embedded tissue was not significantly different before and after weight loss (73 and 69%, respectively). Shrinkage due to the type of embedding of the adipose tissue can be ignored when comparing before and after weight loss. Plastic embedding of adipose tissue provides more accurate and sensitive results.


Assuntos
Tecido Adiposo/patologia , Tamanho Celular , Obesidade , Parafina , Inclusão em Plástico/métodos , Plásticos , Redução de Peso , Adipócitos/citologia , Adipócitos/patologia , Tecido Adiposo/citologia , Adulto , Índice de Massa Corporal , Dieta Redutora , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/dietoterapia , Obesidade/patologia , Reprodutibilidade dos Testes , Inclusão do Tecido/métodos , Adulto Jovem
12.
Am J Physiol Lung Cell Mol Physiol ; 305(5): L364-76, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23831616

RESUMO

Asthma is a chronic inflammatory disease of the small airways, with airway hyperresponsiveness (AHR) and inflammation as hallmarks. Recent studies suggest a role for arginase in asthma pathogenesis, possibly because arginine is the substrate for both arginase and NO synthase and because NO modulates bronchial tone and inflammation. Our objective was to investigate the importance of increased pulmonary arginase 1 expression on methacholine-induced AHR and lung inflammation in a mouse model of allergic asthma. Arginase 1 expression in the lung was ablated by crossing Arg1(fl/fl) with Tie2Cre(tg/-) mice. Mice were sensitized and then challenged with ovalbumin. Lung function was measured with the Flexivent. Adaptive changes in gene expression, chemokine and cytokine secretion, and lung histology were quantified with quantitative PCR, ELISA, and immunohistochemistry. Arg1 deficiency did not affect the allergic response in lungs and large-airway resistance, but it improved peripheral lung function (tissue elastance and resistance) and attenuated adaptive increases in mRNA expression of arginine-catabolizing enzymes Arg2 and Nos2, arginine transporters Slc7a1 and Slc7a7, chemokines Ccl2 and Ccl11, cytokines Tnfa and Ifng, mucus-associated epithelial markers Clca3 and Muc5ac, and lung content of IL-13 and CCL11. However, expression of Il4, Il5, Il10, and Il13 mRNA; lung content of IL-4, IL-5, IL-10, TNF-α, and IFN-γ protein; and lung pathology were not affected. Correlation analysis showed that Arg1 ablation disturbed the coordinated pulmonary response to ovalbumin challenges, suggesting arginine (metabolite) dependence of this response. Arg1 ablation in the lung improved peripheral lung function and affected arginine metabolism but had little effect on airway inflammation.


Assuntos
Arginase/fisiologia , Asma/fisiopatologia , Hiper-Reatividade Brônquica/patologia , Hipersensibilidade/patologia , Pulmão/fisiologia , Pneumonia/patologia , Sistema Respiratório/patologia , Resistência das Vias Respiratórias/fisiologia , Animais , Western Blotting , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/metabolismo , Broncoconstritores/toxicidade , Quimiocinas/metabolismo , Citocinas/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Feminino , Perfilação da Expressão Gênica , Hipersensibilidade/metabolismo , Técnicas Imunoenzimáticas , Pulmão/citologia , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Cloreto de Metacolina/toxicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/citologia , Células Mieloides/metabolismo , Ovalbumina/fisiologia , Pneumonia/induzido quimicamente , Pneumonia/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
PLoS One ; 8(6): e67021, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23785515

RESUMO

Suckling mammals, including mice, differ from adults in the abundant expression of enzymes that synthesize arginine from citrulline in their enterocytes. To investigate the importance of the small-intestinal arginine synthesis for whole-body arginine production in suckling mice, we floxed exon 13 of the argininosuccinate synthetase (Ass) gene, which codes for a key enzyme in arginine biosynthesis, and specifically and completely ablated Ass in enterocytes by crossing Ass (fl) and Villin-Cre mice. Unexpectedly, Ass (fl/fl) /VilCre (tg/-) mice showed no developmental impairments. Amino-acid fluxes across the intestine, liver, and kidneys were calculated after determining the blood flow in the portal vein, and hepatic and renal arteries (86%, 14%, and 33%, respectively, of the transhepatic blood flow in 14-day-old mice). Relative to control mice, citrulline production in the splanchnic region of Ass (fl/fl) /VilCre (tg/-) mice doubled, while arginine production was abolished. Furthermore, the net production of arginine and most other amino acids in the liver of suckling control mice declined to naught or even changed to consumption in Ass (fl/fl) /VilCre (tg/-) mice, and had, thus, become remarkably similar to that of post-weaning wild-type mice, which no longer express arginine-biosynthesizing enzymes in their small intestine. The adaptive changes in liver function were accompanied by an increased expression of genes involved in arginine metabolism (Asl, Got1, Gpt2, Glud1, Arg1, and Arg2) and transport (Slc25a13, Slc25a15, and Slc3a2), whereas no such changes were found in the intestine. Our findings suggest that the genetic premature deletion of arginine synthesis in enterocytes causes a premature induction of the post-weaning pattern of amino-acid metabolism in the liver.


Assuntos
Adaptação Biológica , Animais Lactentes/fisiologia , Arginina/biossíntese , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Aminoácidos/sangue , Aminoácidos/metabolismo , Animais , Argininossuccinato Sintase/genética , Transporte Biológico , Enterócitos/metabolismo , Feminino , Regulação da Expressão Gênica , Intestino Delgado/metabolismo , Masculino , Camundongos , Camundongos Transgênicos
14.
Eur J Gastroenterol Hepatol ; 23(8): 664-70, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21673577

RESUMO

BACKGROUND: A health insurance-initiated programme to improve cost-effectiveness of acid-suppressing drugs (ASDs). AIM: To evaluate the effect of two different interventions of general practitioner support in reducing drug prescription. MATERIALS AND METHODS: A sequential cluster randomized controlled trial with 90 participating general practitioners in a telephone support (TS) group or practice visit (PV) group. TS group received support in phase-1 (first 6 months), but served as control group in phase-2 (6-12 months period). PV group received no intervention in phase-1, serving as the control group for the TS group, but received support in phase-2. Prescription data were extracted from Agis Health Insurance Database. Outcomes were the proportion of responders to drug reduction and the number of defined daily dose (DDD). Differences in users and DDD were analysed using multilevel regression analysis. RESULTS: At baseline, 3424 patients used ASD chronically (211 DDDs, on average). The difference between TS and control groups among responders was 3.2% [95% confidence interval (CI): 0.8; 5.6] and relative risk was 1.26 (95% CI: 1.06; 1.51). The difference between PV and control groups was not relevant (0.4%, 95% CI: -1.99; 2.79 and relative risk: 1.01, 95% CI: 0.82; 1.20). The difference in DDD per patient was -3.0 (95% CI: -8.9; 2.9) and -5.82 (95% CI: -12.4; 0.73), respectively. CONCLUSION: This health insurance company-initiated intervention had a moderate effect on ASD prescription. In contrast to TS, PVs did not seem to reduce ASD prescription rates.


Assuntos
Antiácidos/administração & dosagem , Prescrições de Medicamentos/normas , Seguro Saúde , Atenção Primária à Saúde/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Antiácidos/economia , Análise Custo-Benefício , Esquema de Medicação , Custos de Medicamentos/estatística & dados numéricos , Prescrições de Medicamentos/economia , Prescrições de Medicamentos/estatística & dados numéricos , Uso de Medicamentos/estatística & dados numéricos , Medicina de Família e Comunidade/economia , Medicina de Família e Comunidade/normas , Medicina de Família e Comunidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde/economia , Atenção Primária à Saúde/estatística & dados numéricos , Classe Social , Telefone
15.
J Biol Chem ; 286(11): 8866-74, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21239484

RESUMO

Suckling "F/A2" mice, which overexpress arginase-I in their enterocytes, develop a syndrome (hypoargininemia, reduced hair and muscle growth, impaired B-cell maturation) that resembles IGF1 deficiency. The syndrome may result from an impaired function of the GH-IGF1 axis, activation of the stress-kinase GCN2, and/or blocking of the mTORC1-signaling pathway. Arginine deficiency inhibited GH secretion and decreased liver Igf1 mRNA and plasma IGF1 concentration, but did not change muscle IGF1 concentration. GH supplementation induced Igf1 mRNA synthesis, but did not restore growth, ruling out direct involvement of the GH-IGF1 axis. In C2C12 muscle cells, arginine withdrawal activated GCN2 signaling, without impacting mTORC1 signaling. In F/A2 mice, the reduction of plasma and tissue arginine concentrations to ∼25% of wild-type values activated GCN2 signaling, but mTORC1-mediated signaling remained unaffected. Gcn2-deficient F/A2 mice suffered from hypoglycemia and died shortly after birth. Because common targets of all stress kinases (eIF2α phosphorylation, Chop mRNA expression) were not increased in these mice, the effects of arginine deficiency were solely mediated by GCN2.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Arginase/biossíntese , Arginina/deficiência , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Erros Inatos do Metabolismo dos Aminoácidos/genética , Animais , Animais Lactentes/metabolismo , Arginase/genética , Arginina/genética , Linfócitos B/enzimologia , Hormônio do Crescimento/genética , Hormônio do Crescimento/metabolismo , Doenças do Cabelo/enzimologia , Doenças do Cabelo/genética , Hipoglicemia/enzimologia , Hipoglicemia/genética , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Knockout , Complexos Multiproteicos , Doenças Musculares/enzimologia , Doenças Musculares/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas , Síndrome , Serina-Treonina Quinases TOR
16.
Kidney Int ; 79(9): 1013-25, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21270763

RESUMO

Studies of the primary cilium, now known to be present in all cells, have undergone a revolution, in part, because mutation of many of its proteins causes a large number of diseases, including cystic kidney disease. Bardet-Biedl syndrome (BBS) is an inherited ciliopathy characterized, among other dysfunctions, by renal defects for which the precise role of the cilia in kidney function remains unclear. We studied a cohort of patients with BBS where we found that these patients had a urinary concentration defect even when kidney function was near normal and in the absence of major cyst formation. Subsequent in vitro analysis showed that renal cells in which a BBS gene was knocked down were unciliated, but did not exhibit cell cycle defects. As the vasopressin receptor 2 is located in the primary cilium, we studied BBS-derived unciliated renal epithelial cells and found that they were unable to respond to luminal arginine vasopressin treatment and activate their luminal aquaporin 2. The ability to reabsorb water was restored by treating these unciliated renal epithelial cells with forskolin, a receptor-independent adenylate cyclase activator, showing that the intracellular machinery for water absorption was present but not activated. These findings suggest that the luminal receptor located on the primary cilium may be important for efficient transepithelial water absorption.


Assuntos
Síndrome de Bardet-Biedl/metabolismo , Água Corporal/metabolismo , Cílios/fisiologia , Rim/metabolismo , Absorção , Adulto , Animais , Aquaporina 2/fisiologia , Arginina Vasopressina/fisiologia , Células Cultivadas , Chaperoninas , Colforsina/farmacologia , Células Epiteliais/metabolismo , Chaperoninas do Grupo II/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Receptores de Vasopressinas/fisiologia
17.
Obesity (Silver Spring) ; 19(4): 792-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20595951

RESUMO

Accumulation of triacylglycerols (TAGs) and acylcarnitines in skeletal muscle upon high-fat (HF) feeding is the resultant of fatty acid uptake and oxidation and is associated with insulin resistance. As medium-chain fatty acids (MCFAs) are preferentially ß-oxidized over long-chain fatty acids, we examined the effects of medium-chain TAGs (MCTs) and long-chain TAGs (LCTs) on muscle lipid storage and whole-body glucose tolerance. Rats fed a low-fat (LF), HFLCT, or an isocaloric HFMCT diet displayed a similar body weight gain over 8 weeks of treatment. Only HFLCT increased myocellular TAG (42.3 ± 4.9, 71.9 ± 6.7, and 48.5 ± 6.5 µmol/g for LF, HFLCT, and HFMCT, respectively, P < 0.05) and long-chain acylcarnitine content (P < 0.05). Neither HF diet increased myocellular diacylglycerol (DAG) content. Intraperitoneal (IP) glucose tolerance tests (1.5 g/kg) revealed a significantly decreased glucose tolerance in the HFMCT compared to the HFLCT-fed rats (802 ± 40, 772 ± 18, and 886 ± 18 area under the curve for LF, HFLCT, and HFMCT, respectively, P < 0.05). Finally, no differences in myocellular insulin signaling after bolus insulin injection (10 U/kg) were observed between LF, HFLCT, or HFMCT-fed rats. These results show that accumulation of TAGs and acylcarnitines in skeletal muscle in the absence of body weight gain do not impede myocellular insulin signaling or whole-body glucose intolerance.


Assuntos
Carnitina/análogos & derivados , Gorduras na Dieta/administração & dosagem , Ácidos Graxos/farmacocinética , Intolerância à Glucose/metabolismo , Músculo Esquelético/metabolismo , Triglicerídeos/farmacocinética , Análise de Variância , Animais , Glicemia/metabolismo , Western Blotting , Peso Corporal , Carnitina/metabolismo , Gorduras na Dieta/metabolismo , Diglicerídeos/análise , Metabolismo Energético , Teste de Tolerância a Glucose , Insulina/sangue , Resistência à Insulina , Peroxidação de Lipídeos , Masculino , Músculo Esquelético/efeitos dos fármacos , Ratos , Ratos Wistar
18.
Arch Intern Med ; 170(14): 1264-8, 2010 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-20660848

RESUMO

OBJECTIVE: To evaluate the effectiveness of a health insurance company-initiated intervention strategy aimed at optimizing acid-suppressing drug (ASD) prescriptions in primary care. METHODS: In a cluster randomized controlled trial design, 112 primary care physician (PCP) peer review groups (993 PCPs) in the central region of the Netherlands were randomized. The PCPs in the intervention group received an ASD prescription optimization protocol, a list of their patients taking ASDs frequently on a long-term basis, and financial compensation for additional consultations with these patients. The PCPs in the control group did not receive any of these interventions. Prescription data on 23 433 patients were extracted from the database of the regional health insurance company. The main outcome measures were the proportion of patients who reduced ASD consumption by more than 50% and changes in annual volume and costs of ASD prescriptions. Differences in ASD reduction and in volume were analyzed applying multilevel regression analyses. RESULTS: At baseline, 2.4% of the patients (n = 967 506) of the participating practices used ASDs frequently on a long-term basis (>180 daily defined doses [DDDs] annually). During the 6-month intervention, 14.1% of the patients in the intervention group reduced ASD consumption compared with 13.7% in the control group (adjusted relative risk, 1.04; 95% confidence interval [CI], 0.97-1.11). Changes in intervention and control group in mean volume of ASD prescription per patient were similar (beta = 0.33 for DDD; 95% CI -3.00 to 3.60). CONCLUSIONS: A health insurance company-initiated multifaceted intervention, including practical tools and financial incentives, did not alter ASD prescription practice in primary care. More tailored interventions, including patient-targeted initiatives, are required to optimize ASD prescription.


Assuntos
Prescrições de Medicamentos , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Seguro Saúde , Atenção Primária à Saúde , Idoso , Análise por Conglomerados , Esofagite/tratamento farmacológico , Gastrite/tratamento farmacológico , Refluxo Gastroesofágico/tratamento farmacológico , Antagonistas dos Receptores H2 da Histamina/economia , Humanos , Pessoa de Meia-Idade , Países Baixos , Garantia da Qualidade dos Cuidados de Saúde , Análise de Regressão , Resultado do Tratamento
19.
JAMA ; 302(16): 1782-9, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19861670

RESUMO

CONTEXT: Cardiovascular mortality is considered the main cause of death in patients receiving dialysis and is 10 to 20 times higher in such patients than in the general population. OBJECTIVE: To evaluate if high overall mortality in patients starting dialysis is a consequence of increased cardiovascular mortality risk only or whether noncardiovascular mortality is equally increased. DESIGN, SETTING, AND PATIENTS: Using data from between January 1, 1994, and January 1, 2007, age-stratified mortality in a European cohort of adults starting dialysis and receiving follow-up for a mean of 1.8 (SD, 1.1) years (European Renal Association-European Dialysis and Transplant Association [ERA-EDTA] Registry [N = 123,407]) was compared with the European general population (Eurostat). MAIN OUTCOME MEASURES: Cause of death was recorded by ERA-EDTA codes in patients and matching International Statistical Classification of Diseases, 10th Revision codes in the general population. Standardized cardiovascular and noncardiovascular mortality rates, their ratio, difference, and relative excess of cardiovascular over noncardiovascular mortality were calculated. RESULTS: Overall all-cause mortality rates in patients and the general population were 192 per 1000 person-years (95% confidence interval [CI], 190-193) and 12.055 per 1000 person-years (95% CI, 12.05-12.06), respectively. Cause of death was known for 90% of the patients and 99% of the general population. In patients, 16,654 deaths (39%) were cardiovascular and 21,654 (51%) were noncardiovascular. In the general population, 7,041,747 deaths (40%) were cardiovascular and 10,183,322 (58%) were noncardiovascular. Cardiovascular and noncardiovascular mortality rates in patients were respectively 38.1 per 1000 person-years (95% CI, 37.2-39.0) and 50.1 per 1000 person-years (95% CI, 48.9-51.2) higher than in the general population. On a relative scale, standardized cardiovascular and noncardiovascular mortality were respectively 8.8 (95% CI, 8.6-9.0) and 8.1 (95% CI, 7.9-8.3) times higher than in the general population. The ratio of these rates, ie, relative excess of cardiovascular over noncardiovascular mortality in patients starting dialysis compared with the general population, was 1.09 (95% CI, 1.06-1.12). Relative excess in a sensitivity analysis in which unknown/missing causes of death were regarded either as noncardiovascular or cardiovascular varied between 0.90 (95% CI, 0.88-0.93) and 1.39 (95% CI, 1.35-1.43). CONCLUSION: Patients starting dialysis have a generally increased risk of death that is not specifically caused by excess cardiovascular mortality.


Assuntos
Doenças Cardiovasculares/mortalidade , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Diálise Renal/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Risco , Adulto Jovem
20.
BMC Dev Biol ; 8: 107, 2008 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-19000307

RESUMO

BACKGROUND: Milk contains too little arginine for normal growth, but its precursors proline and glutamine are abundant; the small intestine of rodents and piglets produces arginine from proline during the suckling period; and parenterally fed premature human neonates frequently suffer from hypoargininemia. These findings raise the question whether the neonatal human small intestine also expresses the enzymes that enable the synthesis of arginine from proline and/or glutamine. Carbamoylphosphate synthetase (CPS), ornithine aminotransferase (OAT), argininosuccinate synthetase (ASS), arginase-1 (ARG1), arginase-2 (ARG2), and nitric-oxide synthase (NOS) were visualized by semiquantitative immunohistochemistry in 89 small-intestinal specimens. RESULTS: Between 23 weeks of gestation and 3 years after birth, CPS- and ASS-protein content in enterocytes was high and then declined to reach adult levels at 5 years. OAT levels declined more gradually, whereas ARG-1 was not expressed. ARG-2 expression increased neonatally to adult levels. Neurons in the enteric plexus strongly expressed ASS, OAT, NOS1 and ARG2, while varicose nerve fibers in the circular layer of the muscularis propria stained for ASS and NOS1 only. The endothelium of small arterioles expressed ASS and NOS3, while their smooth-muscle layer expressed OAT and ARG2. CONCLUSION: The human small intestine acquires the potential to produce arginine well before fetuses become viable outside the uterus. The perinatal human intestine therefore resembles that of rodents and pigs. Enteral ASS behaves as a typical suckling enzyme because its expression all but disappears in the putative weaning period of human infants.


Assuntos
Arginina/biossíntese , Argininossuccinato Sintase/metabolismo , Intestino Delgado/enzimologia , Intestino Delgado/crescimento & desenvolvimento , Adolescente , Adulto , Idoso , Arginase/metabolismo , Arteríolas/enzimologia , Arteríolas/metabolismo , Carbamoil-Fosfato Sintase (Amônia)/metabolismo , Criança , Pré-Escolar , Glutamina/metabolismo , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Intestino Delgado/metabolismo , Pessoa de Meia-Idade , Neurônios/enzimologia , Neurônios/metabolismo , Ornitina-Oxo-Ácido Transaminase/metabolismo , Prolina/metabolismo
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